Somerville Scott Alison described his invention of the stethophone at the Royal Society in 1858; the stethophone had two separate bells, allowing the user to hear and compare sounds derived from two discrete locations. This was used to do definitive studies on binaural hearing and auditory processing that advanced knowledge of sound localization and eventually lead to an understanding of binaural fusion. [1] Mc Loughlin MJ and Mc Loughlin S. Cardiac auscultation: Preliminary findings of a pilot study using continuous Wave Doppler and comparison with classic auscultation Int J Cardiol. 2013 Jul 31; 167(2):5 90–91

Stethoscopes 2023 - Medical News Today 7 Best Stethoscopes 2023 - Medical News Today

Here we answer some common questions about stethoscopes. Will a stethoscope hear a fetal heartbeat? The PCE-S 41 Mechanics Stethoscope is battery powered and easy to use. This Mechanics Stethoscope can be used for detecting noise in machine components, such as gears, valves, vents, and pumps. William Hanson, Smart Medicine: How the Changing Role of Doctors Will Revolutionize Health Care, pp. 20–22, Macmillan, 2011 ISBN 0230120938. Matt McFarland, "Eko's stethoscope shows the potential of digital technology to reinvent health care", [1], Washington Post

This dual-headed stethoscope has an open bell and a 3.3-centimeter floating diaphragm with a non-chill rim. The smaller bell and diaphragm may make this product especially beneficial for use on infants and children.

Silverline Mechanics Stethoscope - Screwfix

In 1851, Irish physician Arthur Leared invented a binaural stethoscope, and in 1852, George Philip Cammann perfected the design of the stethoscope instrument (that used both ears) for commercial production, which has become the standard ever since. Cammann also wrote a major treatise on diagnosis by auscultation, which the refined binaural stethoscope made possible. By 1873, there were descriptions of a differential stethoscope that could connect to slightly different locations to create a slight stereo effect, though this did not become a standard tool in clinical practice. Early flexible tube stethoscopes. Golding Bird's instrument is on the left. The instrument on the right is the stethophone. [1]

Several other minor refinements were made to stethoscopes until, in the early 1960s, David Littmann, a Harvard Medical School professor, created a new stethoscope that was lighter than previous models and had improved acoustics. [11] [12] In the late 1970s, 3M-Littmann introduced the tunable diaphragm: a very hard (G-10) glass-epoxy resin diaphragm member with an overmolded silicone flexible acoustic surround which permitted increased excursion of the diaphragm member in a Z-axis with respect to the plane of the sound collecting area. [13] The left shift to a lower resonant frequency increases the volume of some low frequency sounds due to the longer waves propagated by the increased excursion of the hard diaphragm member suspended in the concentric accountic surround. Conversely, restricting excursion of the diaphragm by pressing the stethoscope diaphragm surface firmly against the anatomical area overlying the physiological sounds of interest, the acoustic surround could also be used to dampen excursion of the diaphragm in response to "z"-axis pressure against a concentric fret. This raises the frequency bias by shortening the wavelength to auscultate a higher range of physiological sounds.